Fermented soshiho-tang with Lactobacillus plantarum enhances the antiproliferative activity in vascular smooth muscle cell

BACKGROUND: Soshiho-tang (SST) is a traditional medicine widely used for the treatment of chronic hepatitis. SST has been shown to confer a variety of pharmacological activities, including prevention of hepatotoxicity, promotion of liver regeneration, and modulation of liver fibrosis. In this study, we investigated the antiproliferative activity of native and fermented (FSST) formulations of SST in vascular smooth muscle cells (VSMCs) and examined the potential underlying mechanisms driving these effects. METHODS: SST, along with preparations fermented with Lactobacillus plantarum KFRI-144 (S-A144), L. amylophilus KFRI-161 (S-A161) and L. bulgaricus KFRI-344 (S-A344), were investigated to determine their effects on the proliferation and viability of VSMCs, along with the signalling pathways underlying these effects. RESULTS: S-A144 exhibited a strong, dose-dependent inhibition of VSMC proliferation relative to untreated controls, but the others did not affect. In addition, S-A144 significantly decreased the phosphorylation of Akt and PLCγ1 in a dose-dependent manner and induced cell cycle arrest at the G(0)/G(1) phase characterised by decreased expression of CDKs, cyclins and PCNA. CONCLUSIONS: The findings suggest that S-A144 exhibit enhanced inhibition of PDGF-BB-induced VSMC proliferation comparison to S-AOR through the suppression of cell cycle progression and expression of cell cycle-related proteins, along with the downregulation of Akt phosphorylation.